Exploring smell ability in tracheal intubated patients: An investigation into sniffing proficiency.

Background: Mechanically ventilated patients often experience a loss of smell sensation because of the tubes used in the ventilation process. This can have a significant impact on their overall well-being. As a result, there has been a growing interest in exploring ways to reintroduce and stimulate the sense of smell among these patients.

Aim: To explore the smell ability among tracheal intubated patients and identify the factors influencing olfactory function in this population.

Study design: A prospective cohort study. Data were collected in four adult intensive care units (ICUs) in two hospitals in Egypt. Patients who were intubated via endotracheal or tracheostomy tube with no prior history of olfactory dysfunction were enrolled. Olfactory function was assessed using the Sniffin' Sticks test, which measured odour threshold, discrimination and identification. The test was validated for the Egyptian population through cultural adaptation and test-retest reliability. Statistical analyses, including multiple linear regression and decision tree regression, were utilized to identify significant predictors of olfactory function. This study adhered to STROBE checklist.

Results: A total of 334 adult patients completed the study. Among the patients, 47.0% were classified as anosmic, 48.8% as hyposmic and 4.2% as normosmic. The mean total olfactory score was 17.64 ± 6.01. Older age and the method of oxygen therapy, particularly mechanical ventilation, were significant predictors of reduced olfactory function (p < .001). The decision tree analysis highlighted age as the primary determinant of olfactory performance, followed by the method of oxygen therapy.

Conclusions: This study identified a high prevalence of olfactory dysfunction in tracheal intubated patients and demonstrated that age and oxygen therapy methods are critical factors influencing olfactory function.

Relevance to clinical practice: Recognizing olfactory dysfunction in tracheal intubated patients, may aid in improving patient care, as early detection can lead to better management strategies and improve overall prognosis.